We may have just witnessed a sea change in the business of Parliament. Has anyone noticed?

Vast lakes of ink have been spilled over the past few years in discussing the newly resurgent power of the backbenches in Parliament. Lobby journalists daily sniff the breezes in Portcullis House for the scent of sedition, or trawl through Hansard in a ceaseless quest for amendments of rebellious intent.

But last week witnessed a remarkable new development, which the commentators in all their wisdom have barely noticed. In the passage of the Banking Act, we saw the culmination of a systematic exercise of backbench power that appears to be all but unique in the modern era: not to defeat legislation, but to give it vastly more bite, shape and content.

To see what’s happened, wind the clock back to the summer of 2012. Faced with rapidly escalating public anger over revelations about Libor-rigging at Barclays, the Prime Minister asked Andrew Tyrie MP, Chair of the Treasury Select Committee (of which I am a member), to head up what became the Banking Commission, adding Lords Lawson and Turnbull and the trenchant new Archbishop of Canterbury among others to a core of MPs with relevant experience.

At the time there was huge criticism of this decision. In particular, Ed Miliband denounced it, calling loudly for a judge-led inquiry. The Government rejected this suggestion, on the grounds of delay and cost; and that decision has been triumphantly vindicated. The Commission proved to be energetic, expert, non-partisan and highly independent-minded; and it did its job with great diligence and tenacity. A judge-led inquiry would have taken years and cost millions; but the Commission is already done and dusted, at very modest cost.

But the Commission also acted in a way that justified the Government’s decision in another, more unexpected, sense. Rather than simply file its reports – five great volumes of them – and make its recommendations, it did not let the matter rest there. On the contrary, it vigorously pushed in Parliament to see those recommendations put into law.

On a whole host of issues – issues such as “electrification” of the ring-fence separating commercial and investment banking, leverage ratios for the regulators, proprietary trading, a new criminal sanctions regime for the banks – members of the Commission and the Treasury Committee have actively argued for and promoted improvements to the legislation. Animating the whole has been an insistence on personal responsibility and personal accountability, on the part not merely of bank executives but of the regulators.

Probing amendments were lodged in the Commons; there was much lobbying of ministers behind the scenes; and the Lords took up the issues on their side with great vigour. Some matters, notably reform of the Court of the Bank of England, are still far from fully dealt with. The process faced a good deal of opposition from officials, and was almost certainly irritating, even perhaps at times painful, for the Government. But on the whole it has overwhelmingly succeeded. The Banking Bill, and the Financial Services Bill, have been greatly improved as a result, in all three of their key areas: structural reform of the banks, reform of the regulatory system, and standards of conduct.

How did this happen? It would be easy to see this development as a one-off: the result of all sides pulling together in a serious crisis. So it is, in part. But the process has been greatly enhanced by the election of select committee chairs, which gave the Tyrie Commission a measure of independence and authority from the start. To this was added a long period of scrutiny in the Lords, where a great deal of experience and expertise resides in relation to economic and financial regulation.

These factors point to a potential sea change. Governments will never cease to need rapid and independent scrutiny of major issues thrown up by events – that is the stuff of politics. In some cases a full inquiry led by some judge or grandee will be required. But in others, where what is needed is speed, low cost, expertise and legislative energy, this sets a precedent. It illustrates the age-old rule, that to yield power is often to gain it. And it has allowed Parliament to show itself at its best. Long may it continue.